Protected Plutonium Breeding by Transmutation of Minor Actinides in Fast Breeder Reactor

摘要

The improvement of proliferation resistance properties of Pu and the burnup characteristics of fast breeder reactor (FBR) had been studied by utilizing minor actinides (MAs) to produce more ~(238)Pu from ~(237)Np and ~(241) Am through neutron capture reaction. The higher the ~(237)Pu content in the fuel, the higher the proliferation resistance of the fuel would be owing to the natural characteristics of ~(238)Pu with high decay heat and high neutron production. The present paper deals with the assessment of passive measure against nuclear material proliferation by focusing on improving the inherent proliferation barrier of discharged Pu from an FBR. Results showed that 5% MA doping to the blanket of an FBR gives as high as 17-19% ~(238)Pu, which could be seen as a significant improvement of the proliferation properties of Pu. Moreover, additional 5% ZrH_2, togather with 5% MA doping to the blanket, could enhance the ~(238)Pu fraction much more (22-24%). With an assumption of protected Pu whose ~(238)Pu isotopic fraction is more than 12%, the present paper revealed that protected Pu could be produced more than the Pu consumed (protected Pu breeding) through incineration in an FBR with doping of a minimum 3% MAs or (2% MAs + 5% ZrH2) to the blanket.